This disclosure is in the field of cooling systems for enclosures for apparatus and components that generate heat and electromagnetic radiation, and, more specifically, the field of air valves for enclosures that employ forced air for cooling electronic components.
Electronic components, such as computer systems, are typically housed in a case, chassis, or other enclosure. In a data center, computer system cases may be stacked in a rack, e.g., a rack of servers. Multiple racks may be placed side by side in a row and a data center may have many rows of server racks. The electronic components of computer systems generate heat and system enclosures commonly include one or more cooling fans and associated vents.
Some electronic components generate electromagnetic radiation. The electromagnetic radiation that particular electronic components generate may cause undesirable effects in other electronic components, as well as health effects. With respect to electronic components, these effects are commonly referred to as electromagnetic interference (EMI). It is desirable to ensure that electronic components will not interfere with or prevent the correct operation of other components outside of an enclosure, and will not cause undesirable health effects. Exposure standards, guidelines, and regulations pertaining to electromagnetic radiation generated by electronic components have been developed by various organizations. For example, the U.S. Federal Communications Commission and the European Union have enacted EMI regulations for various products.
Where multiple computer systems are placed in close proximity, e.g., stacked in racks in a data center, the dual needs for cooling and preventing EMI are especially acute. Moreover, methods for addressing these needs may conflict. Cooling needs may call for openings for air to flow into and out of a computer enclosure. Preventing EMI may call for minimizing or eliminating the size of vent openings.